"To be" and its functions. "To have" and its functions

V. State the tense forms of the verbs and translate the sentences:

1. 
   An excessive current will flow until a speed has been reached which will provide a sufficient counter c. m. f. to hold the current down to a normal value.
   
2. 
   The coil will be energized to force the contacts open.
   
3. 
   Power is fed to the commutator through carbon brushes that slide on its surface.
   
4. 
   Some motors are mechanically built for one way rotation only.
   
5. 
   New uses are being found for all types of thermionic tubes.
   
6. 
   All materials are composed of positive and negative charges.
   
7. 
   Automatic and relay operations of all kinds are being made faster and more dependable through introduction of tube control.
   
8. 
   Electrons are emitted by the application of heat to the emitting surface.
   
9. 
   Tungsten and nickel have been considered as the best cathode materials.
   

6. 
   Define the tense-forms of the verbs in the following sentences and translate them
   

1. I have just turned the radio on. 2. Have you listened to the news? 3. He understood the text after he had read it again. 4. I have read this book three times.

5. He has never been to the Carpathians. 6. He has seen this film. 7. Have you ever been to New York? 8. He had finished his work by 5 o'clock yesterday. 9. The technician will have recorded the data before you come. 10. I have not seen him since he graduated from the University. 11. We shall have completed our experiments by the end of the week. 12. My friend had prepared his report before we spoke to you. 13. Electronics has made a rapid progress. 14. He had published his article by the end of the month. 15. We've played lots of matches this season, but we haven't won any. 16. She has spent a great deal of time in the Far East. 17. They'll have finished their work by lunchtime. 18. Have you read anything interesting lately? 19. They've probably forgotten the time. 20. They have accepted the scientist's suggestion. 21. Moscow Radio has been transmitting its programmes to other countries since the thirties. 22. We had been conducting this experiment for two hours before you came. 23. When she arrived, I had been waiting for two and a half hours, 24. It has been raining since two o'clock.

6.